Cannabis and Pregnancy: The Debates

There’s nothing so basic and yet as complicated as pregnancy. While this phenomenon comes naturally to our bodies, the way our habits, environment, and daily lives impact the development of a fetus continues to be mind-boggling to scientists, mothers, and fathers around the world.

More and more, researchers are finding that everyday actions have the ability to affect our bodies and cells at a molecular level. Everything from our diet, our mood, the quality of air that we breathe, and the medications that we take change us slightly in ways that we may not recognize or fully understand.

A Long Way to Go

It’s not surprising, then, that our habits also have an equally complex effect on fetal development. To give a non-cannabis related example, there have been many recent breakthroughs in the field of epigenetics. Simply put, epigenetics is the study of how genes develop and express themselves in ways not dictated by DNA.

When it comes to fetal development, epigenetic researchers have discovered that when women experience high amounts of stress while pregnant, the hormones and stress-related compounds released during pregnancy can lead to changes in the cellular make-up of the fetus, causing the child to be more prone to stress and anxiety in adult life. These traits can even be passed on to further generations.

Though the correlation between prenatal stress and an innate predisposition to anxiety in a child seems like common sense, these recent breakthroughs point out just how much we don’t understand about the science of pregnancy. If researchers are only just now beginning to figure out trends in how our bodies work without introducing another substance or medication, when it comes to throwing something like cannabis into the mix, it’s only logical to assume that the relationship is going to be much more complicated.

The Bad News: THC in Cannabis May Harm Fetal Brain Development

A recent study published in the EMBO Journal found that the active compound in cannabis, THC, may hinder fetal brain development. After performing tests on mice and human brain tissue, researchers found that the presence of THC changes the way that nerve cells communicate and build connections amongst each other.

These changes in neuro-pathways hinder the in utero development of the cerebral cortex in the brain. The cerebral cortex is the part of the brain responsible for memory formation, as well as basic cognitive functions such as attention, creativity, and language. When THC binds to the CB1 receptor of a developing, fetal brain, the cannabinoid blocks the expression of other, much-needed proteins. According to the study, 35 different proteins were affected by the presence of THC in the developing brain.

While the long-term effects and significance of these protein changes are unknown, study researchers such as Professor Harkany of Karolinska Institutet believe that “Even if THC only would cause small changes its effect may well be sufficient to sensitize the brain to later stressors or diseases to provoke neuropsychiatric illnesses in those affected in the future.”

The Good News: Cannabis May Not Actually Harm Fetal Brain Development

The complicated nature of pregnancy studies, especially studies that introduce outside substances or medications like cannabis, means that there are almost always reports that counter or provide a different perspective on the same topic. A 1980s study of Jamaican newborns found that babies that had been exposed to cannabis in utero showed no difference in cognitive functioning and responses to stimuli one day after birth when compared to babies that had not been exposed.

In the study, the researchers looked for differences in things such as alertness, motor function, orientation, regulation of state, and irritability. More interestingly, at one month, the infants exposed to cannabis actually performed better in terms of physiological stability, required less help from the examiner during tests, were more alert, less irritable, and were often considered more rewarding to work with for caregivers.

Five years after this study was performed, researchers returned to examine the original 59 test subjects. The five year follow-up study again found no difference in functioning and ability between those who had been exposed to cannabis as a fetus and those who had not. Rather, differences in children’s ability were strongly correlated to home environment. Children who had access to better schooling and toys tended to perform better on tests than those who did not.

What This Means for Marijuana and Pregnancy

Unfortunately, until cannabis research becomes more widely available to the general population, the exact effects of the plant on infants and brain development will remain a partial mystery. With studies directly contradicting each other, it’s very difficult to make a sound decision about what is actually best for your future child.

Yet, to end on a good note, with medical cannabis becoming a popular alternative to pharmaceutical treatments, we may not have to wait very long for more in-depth medical research on prenatal cannabis consumption. Until then, as with most medications, coffee, and fatty foods, it’s important to review what facts are available and make the decision which you feel is most beneficial to you and your family.

We understand that cannabis and pregnancy is a touchy subject, especially for medical marijuana patients who need to medicate but are also expecting a child. Hopefully, as cannabis continues to gain more mainstream acceptance, more research will become available and we’ll soon be able to better understand the plant’s impact, whether it’s positive, negative, or neutral, on early development.

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